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• Technical procedures and standards for subsequent verification of thermal energy meters are still not available in several EU countries. • Strict error and uncertainty limits are required for thermal energy meters verification. • Relevant deviation between in laboratory and on field results and outcomes have been found. • In laboratory verification shows good reliability at all conditions whereas on the field critical issues arise. Individual metering for heating and cooling has been recognized by EU as an effective tool to improve energy efficiency. Hence, thermal energy meters are widely spreading in district heating networks and in buildings. While type approval and initial verification of thermal energy meters are clearly regulated, no technical standards are available in EU for subsequent verification both in laboratory and in-field. Nevertheless, verification of thermal energy meters is a difficult task, due to the complex measuring chain and to the need to set appropriate verification points combined in flow-rate and temperature difference. In this paper, the authors present the results of an experimental campaign aimed at analysing the metrological issues and compatibility between subsequent verification of a thermal energy meter performed in the laboratory and in-field. The obtained results demonstrate that in-field verification outcomes in some cases are not consistent with the in-laboratory ones. [ABSTRACT FROM AUTHOR]

Electric vehicles as indicated by the recent developments have established a foundation for sustainable transportation. The amount of electricity consumed by the EVs adds a significant amount of loading to the grid. Thus, necessitating the need for simultaneous implementation of vehicle-to-grid infrastructure to protect the grid. In the above circumstances, a bidirectional energy metering system is needed to record the import & export of energy between the grid and the vehicle. Presently the meters are installed on the AC side of the chargers, therefore, losses that occurred during the rectification process are not measured precisely. In this paper, the role of a bidirectional DC measurement system in vehicle-to-grid operation is investigated. The author's aim is to provide accurate billing to end customers by keeping the DC meter on the battery side. In addition, a net metering scheme is implemented to generate the net bill at the end of the billing period. The proposed DC net meter is developed in compliance with the guidelines mentioned in IEC 61000/60255/62052 standards for low voltage applications. It also has a real time clock to implement the Time of Usage (TOU) tariff. The precision of the DC net meter can be seen from the experimental results obtained from the two bench configuration. [ABSTRACT FROM AUTHOR]